Destiny slots for tanks
I would imagine it is the -damage component to Void. I have found it to be nice on the characters I have taken Void with (although I haven't really measured anything, so it could just be that I would have survived fine without the debuff anyway).
Why Blasters? Empathy Sucks.
So, you want to be Mental?
What the hell? Let's buff defenders.
Tactics are for those who do not have a big enough hammer. Wisdom is knowing how big your hammer is.
Follow that up with a Void Judgement power and you are golden. You will be surprised what your Invuln can now do ...hahaha
.